You might like Tamper monkey. You can add a button to kick it off or whatever your heart desires.
Tampermoney also works around CORs issues with relative ease.
Tampermoney also works around CORs issues with relative ease.
Why?
https://github.com/Tampermonkey/tampermonkey
> This repository contains the source of the Tampermonkey extension up to version 2.9. All newer versions are distributed under a proprietary license.